Remove legacy (and also broken) SkPicture constructor.

src/core/SkPicture.cpp

Index: src/core/SkPicture.cpp
diff --git a/src/core/SkPicture.cpp b/src/core/SkPicture.cpp
index 92551d3b1c0c0048950af38161448014ac8ea9cb..6ae1c90e698f9ad92c441940b56024f45d30d509 100644
--- a/src/core/SkPicture.cpp
+++ b/src/core/SkPicture.cpp
@@ -252,15 +252,6 @@ bool SkPicture::Analysis::suitableForGpuRasterization(const char** reason,
 
 ///////////////////////////////////////////////////////////////////////////////
 
-#ifdef SK_SUPPORT_LEGACY_DEFAULT_PICTURE_CTOR
-// fRecord OK
-SkPicture::SkPicture()
-    : fWidth(0)
-    , fHeight(0) {
-    this->needsNewGenID();
-}
-#endif
-
 // fRecord OK
 SkPicture::SkPicture(SkScalar width, SkScalar height,
                      const SkPictureRecord& record,